318iS (1990) Rear Muffler Diameter

["Charles Hebblewhite" <chebblewhite@xxxxxxxxxx>]

I have a 1990 E30 318iS (Australian Version) with a non standard rear
muffler.
The rest of the exhaust system is original (55mm pipe) but I
recall that the factory rear muffler may have 60mm pipe (or larger).
The engine feels a little restricted at 5000rpm.

Can someone tell me the pipe diameter of the original part?

Thanks,
Charles Hebblewhite.

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